Deep dives in a submersible gave scientists a glimpse of mesophotic corals, which survive with surprisingly little light.

"These fish are like candy. They are tiny, colorful bundles of energy that get eaten...by any coral reef organism that can bite, grab, or slurp them up."

Bumphead parrotfish poop helps clarify the relationship between the fish and the reefs they call home.

As oceans warm and get more acidic, corals are under threat. Now, researchers are breeding tougher corals with in vitro fertilization.

For some corals, a little extra heat isn't a big deal. But reefs aren't out of the woods yet.

"Corals and humans both may do well on their own in good times. But when disaster strikes, friends may become essential."

"When done right, these experiences can feel real, and can give learners a lasting sense of connectedness."

Biodiversity on the level of the Central-Indo Pacific Ocean took tens of millions of years. But human impact could wipe it out in less than a decade.